Earth bit



Oct. 21, 1958 S. N. JOHNSON EARTH BIT Filed Aug. 15, 1956 INVENTOR.

Sam N. Johnson AT TORNE Y.

United States Patent EARTH BIT Sam N. Johnson, Denver, Colo. Application August 13, 1956, Serial No. 603,516 4 Claims. (Cl. 255-61) This invention relates to facilities primarily useful to expedite the subterranean installation of pipes serving as flow lines for water, gas, and the like, and more particularly to bit means rotatable in association with the leading end of a pipe member to develop a subterranean bore for the accommodation of the associated pipe, and has as an object to provide a novel and improved construction of such a bit.

A further object of the invention is to provide a novel and improved earth bit particularly adapted for the development of horizontal bores in association with the leading end of a pipe under installation.

A further object of the invention is to provide a novel and improved earth bit characterized by removable, replaceable, and interchangeable blade elements.

A further object of the invention is to provide a novel and improved earth bit characterized by means for jet delivery of water under pressure to the area being worked by the bit.

A further object of the invention is to provide a novel and improved blade element efficient in association with a rotatable body member for the development of earth bores.

A further object of the invention is to provide a novel and improved earth bit that is relatively simple and inexpensive of production, positive and efficient in operation, convenient of repair and rehabilitation, expediently adaptable to use in various locations and situations, and employable to effect material conservation of labor.

With the foregoing and other objects in view, my invention consists in the construction, arrangement, and operative combination of elements as hereinafter set forth, pointed out in my claims, and illustrated by the accompanying drawing, in which- Figure l is a side elevation of a typical embodiment of the invention as organized ready for practical use.

Figure 2 is a bottom plan view of the organization according to Figure 1.

Figure 3 is a top plan view of the organization according to Figure 1.

Figure 4 is a section axially through the organization according to the preceding views taken substantially on the indicated line 4-4 of Figure 3.

Incident to the installation of subterranean gas and water supply lines, particularly those of smaller sizes, and to minimize occasion for trenching, it has become common practice to utilize a bit on and rotatable with the leading end of a pipe section under installation for the development of an earth bore accommodative of the pipe in reaction to rotation of the latter, whereby, as the bore is advanced, additional pipe sections may be coupled to that carrying the bit until the desired full length of line is completed in position of installation within a bore developed through rotation of the line, and it is to the provision of a novel and improved such bit operable with enhanced facility and efficiency that the instant invention is directed.

Sized and proportioned for coaction with a particular size of pipe or line to be installed, the bit of the instant invention is characterized by a solid cylindrical body of hard, rigid material, such as metal, formed to a diameter considerably exceeding that of the line wherewith it is designed to coact and to a length expediently exceeding its diameter. A bore-.11 is formed axially of 2,857,140 Patented Oct. 21, 1958 and entirely through the body 10 in a diametric size less than the interior diameter of the line wherewith the bit is designed to coact, and at one end of said body the axial bore 11 is concentrically enlarged and internally threaded, as at 12, to provide a socket for engagement with the usual threaded end of a flow line in a conventional manner effective to mount the body on and as a coaxial extension of such line with the bore 11 registered as a continuation of the flow passage through the associated line. At its other end, the bore 11 is internally threaded for coaction with the threaded end of a tubular nipple 13 thereby mounted coaxially with and as an extension from the body in direct flow communication with the bore 11, whereby to provide for delivery of flow through the associated line as a jet discharge from the nipple 13 in advance of the end of the body 10 remote from that connected to the line. As will be obvious, rotation of the line threadedly engaged with the body 10 in a direction about its axis such as to tighten the joint between said elements is effective to rotate the body 10 and its nipple 13 against frictions and resistances encountered as the assembly is advanced through the earth.

For the development of an earth bore in reaction to rotation of the body 10 about its axis as above described, said body is equipped with a plurality of identical blade elements 14 angularly spaced peripherally of the body to extend axially therefrom beyond the free end of the nipple 13 in a divergence radially and outwardly of the body, and a significant feature of the invention is the novel organization of said elements in removable and replaceable association with the body. Each of the blade elements 14 is an integral unit of suitable hard, strong metal formed with a rectangular base portion 15 characterized by a length greater than either of its lateral dimensions, which base is adapted to be received and fit closely within an angular pocket, or recess, 16 formed in the periphery of the body 10 to open through the exterior arcuate surface of said body and through the end thereof carrying the nipple 13 in a substantial depth axially of the body approximating one-half the length thereof. As will be manifest, a recess 16 is provided for each of the blade elements 14 utilized with a given body 10, three such blades with their corresponding recesses being represented in the illustrated embodiment of the invention, and the recesses utilized are expediently uniformly spaced apart angularly of the body. The base portion 15 of each blade element 14 is formed with spaced holes adapted to register with internally-threaded holes in and radially of the body 10 opening through the floor, or inner wall, of each recess 16, whereby screws 17 loosely through the holes of the base portion and threadedly engaged with the holes in the body are applied to removably and replaceably secure each of said blade elements to and in desired operative relation with the body.

From its base portion 15, each blade element 14 extends, generally longitudinally of the base portion, as a spiraled web 18 gradually and outwardly diminishing in thickness and gradually and outwardly increasing in width to terminate in a thin cutting lip 19 aligned substantially radially of the body 10. The identical webs 18 of the several blade elements 14 are longer than the projection of the nipple 13 from the body 10 and spacedly surround said nipple with their lips 19 outwardly from said body well beyond the free end of the nipple, and each of said webs is longitudinally curved to advance its lip 19 in the direction of bit rotation and to oil-set said lip radially and outwardly of the body 10 for extension of the lip outer corner well beyond the projected outline of the body, whereby said lips are adapted to track in an annular path concentric with and ahead of the associated body 10 characterized by a outer diameter greater than that of said body and an inner diameter less than that of the body. The lips 19 terminating the Webs are worked in; any appropriate manner to condition them to. out: through; material against. which. they are advanced. -5: the; bit assembly is-rotated,.a.par-

if. req isite, he bit. isengaged by meansbf. its body. l0.-

to the; leading end-. fta short lengthiofspipewhich is connectedin. any expedient manner toreceive water underpressllr sand the;linn;andf bit: are then rotated with the bit advanced, against the; earth. while, water flowsv therethrough to ie dischargezata the; free end! of the nipple 13;

As the bit rotates, withv the. line; the blade elements 1.4.

thereofexcav-atean. annular trough about a central core that disintegrates and breaks away under. the influence of. the jet directed thereagainst, thusto develop: a. bore. wherein and wherethrough the advancing line is, freely accommodated. Asqthez boroadyances, additionaltlengths of' lineare successively added to the initial length until aninstallation: of; desiredlength is completed, whereafter the watersupply is; disconnected; from the line, the bit removed from the leading. end. of the installed line, andthe latter is; then; in place and; condition for: connection in and with a-servicesystem;

Since changes, variations, and modifications in the form, construction, and arrangement of the elements shown and; described may be had without departing'from the spirit of my. invention, I wish to. be understood as being-,limitedsolely by-the scope, of the appended claims,

rather than by any details of the illustrative showing and foregoingdescriptiom Ia claim as my invention:

1. An earth bit comprising a cylindrical body formed at one end. with a coaxial socket threadedly engagcable with the leading. end of a pipe and with an axial flow passage small in relation to the size of said socket, a nipple; projectingfrom the end ofv said body remote from said; socket in. aligned. registration with and as a continuation: of said: flow passage, like, angular recesses opening exteriorly and. peripherally of the body and through; the endthereof carrying said'nipple-in'anangular spacing theteabout; and an. excavating: blade independently and: detachably secured at one end in each. of; said; recesses. in surface conformity with the body to extend? longitudinally therefrom in an outward diver gence from the axis. thereof spacedly about and beyond the freenend Qf: the,nipple,wherein=eachtof said'blades comprises. a rectangular-base portion adapted for fitted engagement. within one of; said recesses and an integral, spiraled web extending from one end of said base portionbetween outwardly-divergent side margins a distance greater than the. length of said nipple and terminating in a transverse lip. adapted to lie radially of and at a spacing outwardly from the axis of the body whereto the bladeis secured.

2. An. earth bit comprising a cylindrical body formed atone end with, a coaxial socket threadedly engageable with the leading end of a pipe and with an axial flow passage small in. relation to the size of said socket, a nipple projecting from the end of said body remote from said socket in aligned registration with and as a-continuation of;-saidfiow passage, like, angular recesses opening exteriorly and. peripherally. of the body andithrough the end thereof carrying saidnipple in an: angular spacing thereabout, andan excavating blade independently and detachably secured at one. end in each of said recesses in surface conformity withtthe body to extend longitudie nally therefrom in an outward divergence from theaxis.

thereof spacedly about and beyond the free end of the nipple, wherein each of said blades comprises a rectangular base portion adapted. forfitted engagement within one of said recesses and an integral, spiraled web 1011'- gitudinally and outwardly divergent as to width and convergent as to thickness extending from: one; end of said base portion a distance greater than the length. of said nipple and terminating in a transverse lip adapted to lie radially of and at a spacing outwardly from the axis of the body whereto the blade is secured.

3. An earth bit comprising a cylindrical body formed at one end with a. coaxial socket threadedly engageable: with the leading end of a pipe and with an. axialiflow' passage small in relation tov the: size of said socket; a

nipple projecting from the end of'said body remote from: said socket in aligned registration with and as. a contmuation of said flow passage, like, angular recesses-opening exteriorly an'd peripherally of the body and. through the end. thereof carrying said nipple in an. angular spacing thereabout, and an excavating: blade independently and detachably secured at one end' in. each of said recessesin' surface conformity-with thebody. to extend longitudinally. therefrom in an outward divergence from the axis thereof spacedly'about and beyond the freeend of: the nipple,

wherein each. of said bladescomprises a rectangular:

base portion adapted; fon fitted engagement within-one of said recesses, an. integral, spiralede web longitudinale ly and outwardly divergent as. to. width and convergent as to thickness extending from one end of said base a distance; greater-than the. length of saidnipple, said web being formed to diverge arcuately. outwardly and radially awayfrom. the axis of the associated: body with. its free end arcuately advanced in the direction of body rotation relative to the connection. between the blade and body, and a transverselip at the free end of said web. adapted to lie radially of and at a spacing outwardly from thetaxis of the body whereto.'theblade is secured.

4. An earth'bit comprising a cylindrical bodyformed at one end with. a. coaxial socket threadedly engageable.

with: the. leading end oft a pipe and; with. an axial flow passage 51113111 in relation to. the size of. said; socketga nipple projecting from: thetend of saidbody remote from said. socket. in; aligned; registration. with. and as a; con

tinuation of said flow passage, like, angular recesses opening: exteri'orly and peripherally of the.- body and throughthe: end-.thereofcarrying said: nipple in an angu.- t

larspacing thereabout, and an excavating blade independently and detachably secured atone end in each ofi said; recesses in surface; conformity with the body: to

extend longitudinally therefrom in an outward divergence;

curvature. in two, directionsetfective. to advance said lip.

in the direction ofbit rotation beyond the connection. be.-

tween the. blade. and, body and; to. ofiset' said lip radially.

an'd. outwar y frQmthe-axis of; the associated body;

References Cited in the file of this patent UNITED STATES PATENTS 854,464 Charlton a"-.. May'2l, 1907 1,881,024 Lang. Oct; 4, 1932 1,950,101 Dixon Mar; 6, 193.4. 2,599,854 McMurdy et a1., June. 10, 1952 FOREIGN PATENTS 247,472 Great Britain Feb. 18, 1 926 

